1. Field of the Invention
The present invention relates to a deflection yoke device, and in particular to a deflection yoke device equipped with magnetic leakage-protecting coils.
2. Description of the Prior Art
Recent studies indicate that magnetic leakage from a cathode ray tube of a deflection yoke in a television receiver set or display apparatus adversely affects the human body, especially pregnant women. Attempting to address this problem, some protective measures have been taken to minimize the magnetic leakage from the deflection yoke. FIG. 1A is a deflection yoke device equipped with magnetic leakage-protecting coils which protect against magnetic leakage.
A magnetic leakage protecting coil 12 shown in FIG. 1A is formed such that, as shown in FIG. 1B, an adhesive-coated copper wire 1, which is coated with an adhesive layer made of a thermoplastic resin or the like, is wound ring-wise forming a coil. The coiled wire is then current-heated so as to melt the adhesive layer thereby forming an integrally united coil made of plural coiling rings. The united coil is fitted in a coil bobbin 2 as shown in FIG. 1C to complete the magnetic leakage protecting coil 12. Alternatively, the coil 12 may be composed of a square or ring-shaped bobbin which is formed in advance with a wire wound thereon by a flyer method. Lead wires extracted from the coil 12 are drawn outside from the coil bobbin 2 as shown in FIG. 1D. These lead wires are cut to a desired length for connection. The distal end portions required for soldering are abraded or processed in another way for terminal treatment while the other portion is covered by an insulating tube 3.
A couple of the thus formed magnetic leakage-protecting coils 12 are mounted to a bobbin portion 11 of a deflection yoke 5 by snap-mounting means, adhesive means or any other engaging means. One coil is mounted at a top side and the other at a bottom side of an enlarged diameter portion 4 of a head portion 9 of the bobbin 11. Further, a printed wiring board 6, having an appropriate number of connect pins 7 ,are located on a neck portion of the deflection coil 5. The pins 7 are twined and soldered with lead lines extracted from the coils 12 to thereby complete a deflection yoke device in which the coil of the deflection yoke 5 is connected with the magnetic leakage-protecting coils 12.
However, in the prior art example described above, complicated, manual assembling is required which comprises the steps of fitting the wound coils in the coil bobbins 2, cutting the lead wires of the coils to a predetermined length, treating the ends of the wires, covering each of the extracted lead wires with the tube 3 and twining the wires with respective pins 7 so that the wires may be soldered to the pins 7. Further, because the two magnetic field leakage protecting coils 12 are manually connected with each other through the pins 7 disposed on the deflection yoke 5, this structure allows mis-connection between the two coils 12.